NEW YORK — Police handcuffed dozens of protesters in cities around the country today as they blocked traffic in the latest attempt to escalate their efforts to get McDonald’s, Burger King and other fast-food companies to pay their employees at least $15 an hour.

The protests, which were planned by labor organizers for about 150 cities nationwide throughout the day today, are part of a campaign called “Fight for $15.”

Since the protests began in late 2012, organizers have switched up their tactics every few months to bring attention to the protests, which have attracted spotty crowds. Organizers previously said they planned to engage in nonviolent civil disobedience today, which might lead to arrests. In the past, supporters have done things like show up at a McDonald’s shareholder meeting and hold overseas protests.

The movement, which is backed financially by the Service Employees International Union and others, comes at a time when the wage gap between the poor and the rich has become a hot political issue. Many fast-food workers do not make much more than the federal minimum wage of $7.25 an hour, which adds up to about $15,000 a year for 40 hours a week.

The protests have gotten media coverage. In Chicago, for instance, reporters observed supporters arriving on buses and sitting on a street between a McDonald’s and Burger King, chanting: “We shall not be moved.”

“The impact is in bringing it into the public attention,” said Chris Rhomberg, an associate professor of sociology at Fordham University in New York.

President Obama has taken notice too. He mentioned the campaign at a Labor Day appearance in Milwaukee. “If I were busting my butt in the service industry and wanted an honest day’s pay for an honest day’s work, I’d join a union,” Obama said, as he pushed Congress to raise the minimum wage.

The National Restaurant Association said in a statement that the protests are an attempt by unions to “boost their dwindling membership.” The industry lobbying group said it hopes organizers will be respectful to customers and workers during the protests.

Union organizers expected thousands to show up to today’s protests around the country. Previously, turnout has been fairly minimal in many places. In an effort to get more people involved, organizers asked other service workers to join protests and added more cities than it previously had.

Shanicka Primo, who was at a protest at McDonald’s in New York, said she heard about the demonstration after organizers came to the Checkers restaurant where she works. The 20-year-old earns $8 an hour at the burger chain and said a raise to $15 per hour would help her get her own apartment. “I wouldn’t have to live with my family,” Primo said.

Carmalita Johnson drums as protesters participate in a rally outside a McDonald’s on Chicago's south side today as labor organizers escalate their campaign to unionize the industry's workers.

In some cities, protesters were hauled away by police for blocking streets. Police handcuffed about a dozen people who wouldn’t leave in Chicago.

In New York, at least three people wearing McDonald’s uniforms were taken by police officers after standing in the middle of a busy street near Times Square. Nineteen were arrested for blocking traffic.

About 100 protesters marched through the parking lot of an east-side McDonald’s before dawn today, shouting slogans and clogging the drive-thru lane. Some sat in the street, and officers handcuffed those who wouldn’t move.

Detroit police say they ticketed 24 protesters for disorderly conduct and released them. Police say they arrested six on outstanding traffic warrants.

Among those hauled away was Tyree Johnson. He said he earns $8.45 an hour after working at a Chicago McDonald’s for more than two decades. “I’ve been there 22 years and I can’t help my family,” he said.